In short: Your aim can now be off target, On Target within 500 feet or 250 feet of your target. If you are On Target (250 feet) roll for accuracy on TZ-5, On Target 250 feet.
Please let me know how this works for you and if you have any ideas on how to improve this idea.
See also http://themarauderstrikes.magnuskimura.se/#post66 (9th Air Force Bombing Accuracy.)
Less than 70% - see 500 feet & %
Less than 20% - see Off Target & %